. Elements of botany. Plants. Fig. 193.— Process of Cell-3rulti- plication in a Species of Pond- scum. (Considerably magnified.) A, portion of a filament partly separated at a and completely so at 6 ; B, separation nearly com- pleted, a new partition of cellu- lose formed at a; C, another portion, more magnified, show- ing mucous covering d, general cell wall c, and a delicate mem- brane a, which covers the cell- contents Fig. 194. — Unicellular Fresh-Water Plants (), forming Spores by Conjugation. (Much magnified.) A, a single plant in its ordinary condition ; B, empty cell wall
. Elements of botany. Plants. Fig. 193.— Process of Cell-3rulti- plication in a Species of Pond- scum. (Considerably magnified.) A, portion of a filament partly separated at a and completely so at 6 ; B, separation nearly com- pleted, a new partition of cellu- lose formed at a; C, another portion, more magnified, show- ing mucous covering d, general cell wall c, and a delicate mem- brane a, which covers the cell- contents Fig. 194. — Unicellular Fresh-Water Plants (), forming Spores by Conjugation. (Much magnified.) A, a single plant in its ordinary condition ; B, empty cell wall of another individual ; C, conjuga- tion of two individuals to form a spore by union of their cell-con- tents. develops. In Spirogyra each cell of the filament appears to be an individual and can conjugate like the one-celled desmids. It is not easy to watch the process, since the growth of the filaments goes on mainly by day, in sunlight, and the spore-formation takes place at night, when gi'owth is less rapid. It is possible, however, to retard the occurrence of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bergen, Joseph Y. (Joseph Young), 1851-1917; Bergen, Joseph Y. (Joseph Young), 1851-1917. Bergen's Botany: key and flora, Pacific coast ed. Boston : Ginn
Size: 1694px × 1474px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectplants, bookyear1896
